Proton-magnetic resonance lines in liquid crystalline p[(p-methoxybenzylidene) -amino]benzonitrile, p-[(p-ethoxybenzylidene) -amino]benzonitrile, and p-[(p-ethoxybenzylidene)amino]phenyl acetate

Abstract

Experimental linewidth (2.4 to 3.4 G) vs temperature measurements are given for the broad NMR signals of p-[(p-methoxybenzylidene) -amino]benzonitrile (PMBAB) and linewidth (2.7 to 3.7 G) vs temperature measurements for the broad NMR signal of p-[(p-ethoxybenzylidene) -amino]benzonitrile (PEBAB). For the very broad five peak line of p-[(p-ethoxybenzylidene)amino]phenyl acetate (PEBAP) both inner linewidth peak separation (3.1 to 3.7 G) and outer peak separation (5.8 to 7.3 G) are given as a function of temperature. All three of the above compounds have the same central chemical structure yet the first two give a three peak line and the last a five peak line. Explanation of these outer lines is given. Also, for each substance graphs of order parameters vs temperature ranging from 0.57 to 0.68 for PEBAB and 0.45 to 0.62 for PMBAB and 0.56 to 0.67 for PEBAP are given.